JPH06107758A - Novolak derivative, epoxy resin, epoxy resin composition for sealing for sealing semiconductor using the same and semiconductor device - Google Patents

Abstract

PURPOSE:To obtain a novolak derivative capable of providing a semiconductor device having improved characteristics to be evaluated by TCT test and excellent crack resistance during being immersed in a solder melt, an epoxy resin, an epoxy resin composition for sealing semiconductor using the epoxy resin and a semiconductor device. CONSTITUTION:A novolak derivative comprises at least one of components (A) a novolak derivative of monohydroxyanthracene, (B) a novolak derivative of dihydroxyanthracene and (C) a novolak derivative of trihydroxyanthracene as a main component. The components (A), (B) and (C) have 80-220 hydroxyl equivalent and 70-200 deg.C softening temperature. An epoxy resin composition for sealing semiconductor containing the novolak derivative having the characteristics is used to seal a semiconductor element.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novolac body used for manufacturing a semiconductor device having excellent reliability, an epoxy resin, an epoxy resin composition for semiconductor encapsulation using the same, and a semiconductor device. .

[0002]

2. Description of the Related Art Conventionally, semiconductor elements such as transistors, ICs, and LSIs have been sealed by a ceramic package or the like to be a semiconductor device, but recently, from the viewpoint of cost and mass productivity, a resin using a plastic package is used. Sealing is the mainstream. Epoxy resin has been used for this type of resin encapsulation and has achieved good results. However, due to technological innovation in the semiconductor field, the degree of integration has improved, the device size has become larger, and the wiring has become finer, resulting in smaller and thinner packages.
Along with this, there is a demand for further improvement in reliability of the encapsulating material (recommendation of thermal stress of the obtained semiconductor device, moisture resistance reliability, reliability in thermal shock test, etc.). In particular, in recent years, the size of semiconductor elements has tended to become larger and larger, and there is a demand for further improvement in performance with respect to a thermal cycle test (TCT test) which is an accelerated test for evaluating the performance of a semiconductor encapsulating resin. Surface mounting is becoming the main method of mounting semiconductor packages.Therefore, it is required that the package does not crack or swell even if it is dipped in a solder melt after absorbing the moisture. ing. In this regard, TC
In order to improve each property evaluated in the T test, it has been considered to modify the epoxy resin with a silicone compound to reduce the thermal stress. Also, in order to improve the crack resistance when dipping the solder, the lead frame and The improvement of the adhesion has been studied, but the effect is not yet sufficient.

As described above, the epoxy resin compositions for encapsulation hitherto have not been sufficiently satisfactory in the results of the TCT test and the crack resistance characteristics when immersed in solder. For this reason, it is strongly desired to improve both of the above characteristics so as to be able to cope with the increase in the size of semiconductor elements and the surface mounting due to the above technical innovation.

The present invention has been made in view of the above circumstances, and it is possible to obtain a novolac capable of obtaining a semiconductor device having improved characteristics evaluated in a TCT test and excellent crack resistance when immersed in a solder melt. The object is to provide a body, an epoxy resin, an epoxy resin composition for semiconductor encapsulation using the same, and a semiconductor device.

[0005]

In order to achieve the above object, the present invention provides a novolac body containing at least one of the following (A), (B) and (C) as a main component, (A), (B) and (C) have a hydroxyl group equivalent of 80 to
A novolac body having a characteristic of being in the range of 220 and having a softening temperature of 70 to 200 ° C. is defined as a first gist, and (A) a monohydroxyanthracene novolak body. (B) A novolac form of dihydroxyanthracene. (C) A novolac form of trihydroxyanthracene. A second gist is an epoxy resin obtained by reacting the novolac body with epichlorohydrin. In addition, a third embodiment of an epoxy resin composition for semiconductor encapsulation containing an epoxy resin, a curing agent composed of the above novolak body, and a curing accelerator.
According to a fourth aspect of the present invention, there is provided a semiconductor encapsulating epoxy resin composition containing the above epoxy resin, a curing agent, and a curing accelerator.
The fifth gist is an epoxy resin composition for semiconductor encapsulation containing the epoxy resin, a curing agent composed of the novolac body, and a curing accelerator. Further, a semiconductor device obtained by encapsulating a semiconductor element using the epoxy resin composition for semiconductor encapsulation which is the third gist is a sixth gist, and the epoxy resin composition for semiconductor encapsulation which is the fourth gist. A semiconductor device in which a semiconductor element is sealed with
A semiconductor device obtained by encapsulating a semiconductor element using the epoxy resin composition for semiconductor encapsulation, which is the fifth aspect, is the eighth aspect.

[0006]

In other words, the present inventors have conducted a series of studies in order to improve the respective properties evaluated by the TCT test and the crack resistance when immersed in a solder melt.
As a result, when at least one of a monohydroxyanthracene novolak body (A), a dihydroxyanthracene novolak body (B) and a trihydroxyanthracene novolak body (C) having a certain property is used as a sealing material, a sealing resin is obtained. The present inventors have found that an anthracene skeleton is formed in the main skeleton, and that the TCT test and the crack resistance when immersed in a solder melt after moisture absorption are excellent, and the present invention has been reached.

Next, the present invention will be described in detail.

In the present invention, the novolac body which is the basis of the semiconductor encapsulating material is composed mainly of at least one of the following (A), (B) and (C), A), (B) and (C) have a hydroxyl group equivalent of 80 to 220 and a softening temperature of 70 to 2
It must have the property of being 00 ° C. In addition, the above-mentioned "being a main component" is intended to include a case where only the main component is included. (A) A novolac form of monohydroxyanthracene. (B) A novolac form of dihydroxyanthracene. (C) A novolac form of trihydroxyanthracene.

Examples of the monohydroxyanthracene include 1-hydroxyanthracene, 2-hydroxyanthracene and 9-hydroxyanthracene. Further, as the above dihydroxyanthracene,
Specifically, 1,4-dihydroxyanthracene, 9,1
Examples thereof include 0-dihydroxyanthracene, and as the above-mentioned trihydroxyanthracene, 1,2,10-trihydroxyanthracene, 1,8,9-trihydroxyanthracene, 1,2,7-trihydroxyanthracene and the like are preferably used. To be These may be used alone or in combination. Then, a novolak body is produced by performing condensation using the above compound and an aldehyde component. In this case, the degree of condensation is preferably in the range of 2-5. Also,
Examples of the aldehyde component include formaldehyde and the like, but are not particularly limited, and aldehydes other than the above may be used. In this manufacturing method, the raw materials anthracene (X) and formaldehyde (Y) are mixed in a weight ratio of X: Y = 100: 70 to 100: 55, and reacted at about 100 ° C. using hydrochloric acid as a catalyst. The product is concentrated as it is, crushed after cooling and solidified. As described above, the TCT test of the package using the sealing resin using the special skeleton, and the hydroxyl group equivalent and the softening temperature only within the above ranges, and the crack resistance when immersed in the solder melt. Is improved. That is, when the hydroxyl equivalent and the softening temperature are out of the above ranges,
This is because the mixing ratio of the epoxy resin and the curing agent deviates from a good balance state, and the desired performance cannot be exhibited.

The epoxy resin composition for semiconductor encapsulation of the present invention has the following three modes depending on the combination of the epoxy resin constituting the main component and the curing agent. Then, a curing accelerator is added to each of the above three types of modes.

The first aspect is a combination of a special epoxy resin and a usual curing agent, and the second aspect is a combination of a usual epoxy resin and a special curing agent.
The third aspect is a combination of a special epoxy resin and a special curing agent. The epoxy resin composition for semiconductor encapsulation composed of such a combination is usually in the form of a powder or a tablet obtained by tableting the same.

First, the first mode will be described.

The special epoxy resin used in the first embodiment is a glycidyl ether obtained by reacting a novolac body containing at least one of (A), (B) and (C) as a main component with epichlorohydrin. It can be obtained by In this glycidyl etherification reaction, epichlorohydrin is reacted with the hydroxyl group of the produced novolak body to form glycidyl ether. This is because the latter is set excessively and both are mixed and reacted at about 100 ° C. Then, the product is washed with water to remove excess epichlorohydrin and generated hydrochloric acid. Above all, the epoxy equivalent of 130-
It is preferable to use one having a softening point of 280 and a softening point of 50 to 150 ° C.

Examples of the curing agent used together with the above-mentioned special epoxy resin include ordinary novolac type phenolic resins, specifically phenol novolac,
Cresol novolac resin and the like are preferably used. It is preferable to use those novolak resins having a softening point of 50 to 110 ° C. and a hydroxyl equivalent of 70 to 150. Particularly, it is preferable to use a phenol novolac resin among the above novolak resins.

The mixing ratio of the above-mentioned special epoxy resin and the curing agent is such that the hydroxyl groups in the curing agent are 0.8 to 1.2 equivalents per equivalent of epoxy groups in the above-mentioned special epoxy resin. Is preferred.

The curing accelerator to be used with the above-mentioned special epoxy resin and curing agent is not particularly limited, and conventionally known ones, for example, triallylphosphine compounds such as triphenylphosphine, tertiary amines and quaternary ammonium salts. , Imidazoles and boron compounds. These may be used alone or in combination.

The inorganic filler used together with the above-mentioned special epoxy resin, curing agent and curing accelerator is not particularly limited, and commonly used quartz glass powder, talc, silica powder, alumina powder and the like can be mentioned. . It is particularly preferable to use silica powder. The content of such an inorganic filler, in the case of silica powder,
It is preferably set to 50% by weight (hereinafter abbreviated as “%”) or more based on the entire epoxy resin composition. It is more preferably 70% or more, and particularly preferably 75% or more.
That is, if the content of the inorganic filler is less than 50%, the effect of containing the filler tends to be significantly reduced.

Next, the second aspect will be described.

The usual epoxy resin used in the second embodiment is not particularly limited to the molecular weight, the molecular structure and the like as long as it has two or more epoxy groups, and a conventionally known one can be used. For example, bisphenol A
Type, phenol novolac type, cresol novolac type and the like are used. Among these resins, those having a melting point above room temperature and exhibiting a solid state or a highly viscous solution state at room temperature give good results. The novolac type epoxy resin is usually an epoxy equivalent of 160 to 25.
A resin having a softening point of 50 to 130 ° C. is used, and a cresol novolac type epoxy resin has an epoxy equivalent of 1
Those having a softening point of 80 to 210 and a softening point of 60 to 110 ° C. are generally used.

As the special curing agent used together with the usual epoxy resin, a novolac body containing at least one of (A) and (B) as a main component is used.

The compounding ratio of the ordinary epoxy resin and the special curing agent (novolak body of the present invention) is the same as in the first embodiment, and the special curing agent is equivalent to 1 equivalent of the epoxy group in the ordinary epoxy resin. It is preferable that the hydroxyl groups in the mixture be 0.8 to 1.2 equivalents.

The curing accelerator and the inorganic filler used together with the usual epoxy resin and the special curing agent are the same as those in the first embodiment, and the contents should be set to the same ratio. Is preferred.

Next, the third aspect will be described.

The third aspect is a combination of a special epoxy resin and a special curing agent, and the special epoxy resin, the special curing agent, the curing accelerator and the inorganic filler are also used in the first aspect. And the same as those used in the second aspect.

In the first to third embodiments, when the above-mentioned special epoxy resin is used as the epoxy resin component, the conventional epoxy resin is used together in a proportion of 50% or less of the whole epoxy resin component. Good. When using the above-mentioned special curing agent as the curing agent component,
Similar to the epoxy resin component, a conventionally used ordinary curing agent may be used in combination at a ratio within 50% of the entire curing agent component. That is, when the content of the usual epoxy resin and the usual curing agent exceeds 50% of the total amount of each component, it is difficult to obtain the desired effect of improving each characteristic evaluated by the TCT test.

Further, it is effective to use a silicone compound in combination with the epoxy resin component, the curing agent component, the curing accelerator and the inorganic filler used in the first to third aspects. Examples of the silicone compound include those represented by the following general formulas (1) and (2), which may be used alone or in combination.

[0027]

[Chemical 1]

The blending amount of such silicone compound is
It is preferable to set the silicone compound to be 5% or less of the total epoxy resin composition. It is particularly preferably in the range of 0.5 to 3.0%. That is, when the compounding amount of the silicone compound exceeds 5%, properties such as heat resistance tend to be deteriorated.

The epoxy resin composition for semiconductor encapsulation of the present invention contains, in addition to the epoxy resin component, curing agent component, curing accelerator, inorganic filler and silicone compound used in the first to third aspects. If necessary, flame retardants such as antimony trioxide and phosphorus compounds, pigments, coupling agents such as silane coupling agents, and the like can be used.

The epoxy resin composition for semiconductor encapsulation of the present invention can be manufactured, for example, as follows. That is, the epoxy resin component, the curing agent component, the curing accelerator and the inorganic filler used in the first to third aspects, and in addition to these, a silicone compound, and if necessary, a flame retardant, a pigment and a coupling agent. Blend at a predetermined ratio. Then, the mixture is subjected to a kneader such as a mixing roll machine, melt-kneaded in a heated state, cooled to room temperature, pulverized by a known means, and optionally tableted by a series of steps. The epoxy resin composition for semiconductor encapsulation can be obtained.

The encapsulation of a semiconductor element using such an epoxy resin composition for encapsulating a semiconductor is not particularly limited, and may be performed by a known molding method such as ordinary transfer molding or casting method. it can.

[0032]

INDUSTRIAL APPLICABILITY As described above, the present invention provides at least one of a monohydroxyanthracene novolak compound (A), a dihydroxyanthracene novolak compound (B) and a trihydroxyanthracene novolak compound (C) having certain properties. Is used as a curing agent or is encapsulated with an epoxy resin composition for semiconductor encapsulation obtained by using the same, the characteristics evaluated by the TCT test are improved and the life is extended. . Also, package cracks are less likely to occur even when immersed in a solder melt after absorbing moisture. Furthermore, by encapsulating with the above-mentioned special epoxy resin composition for encapsulating semiconductors,
Especially with 16 pins or more or the long side of the semiconductor element is 4 m
The above-described high reliability can be obtained in a large-sized semiconductor device having a size of m or more, which is a major feature.

Next, examples will be described together with comparative examples.

Prior to the production of the epoxy resin composition for semiconductor encapsulation, the following silicone compounds a to d, epoxy resins A to G and curing agents A to G were prepared.

[Silicone compound a]

[Chemical 2] Epoxy equivalent: 1800

[Silicone compound b]

[Chemical 3] Epoxy equivalent: 3000

[Silicone compound c]

[Chemical 4] Epoxy equivalent: 7,000

[Silicone compound d]

[Chemical 5] Amine equivalent: 3800

In the above silicone compounds a to d, the value of n is 40 for the silicone compound a, 60 for the silicone compound b, and 29 for the silicone compound c. The value of X is 152 for the silicone compound c and 148 for the silicone compound d. The value of Y is 3 for both the silicone compound c and the silicone compound d. The value of Z is 5 for the silicone compound c.

[Epoxy Resin A] 1,4-Dihydroxyanthracene represented by the following structural formula was converted into novolak with formaldehyde.

[Chemical 6] Then, this was reacted with epichlorohydrin to form glycidyl ether. Epoxy equivalent: 175, softening temperature: 120 ° C

[Epoxy Resin B] 9,10-dihydroxyanthracene represented by the following structural formula was converted into novolak with formaldehyde.

[Chemical 7] Then, this was reacted with epichlorohydrin to form glycidyl ether. Epoxy equivalent: 175, softening temperature: 118 ° C

[Epoxy Resin C] 1,2,10-trihydroxyanthracene represented by the following structural formula was converted into novolak with formaldehyde.

[Chemical 8] Then, this was reacted with epichlorohydrin to form glycidyl ether. Epoxy equivalent: 142, softening temperature: 102 ° C

[Epoxy Resin D] 1-Monohydroxyanthracene represented by the following structural formula was novolaked with formaldehyde.

[Chemical 9] Then, this was reacted with epichlorohydrin to form glycidyl ether. Epoxy equivalent: 262, softening temperature: 95 ° C

[Epoxy resin E] A mixture of 1,4-dihydroxyanthracene and 1,2,10-trihydroxyanthracene [mixing ratio (weight ratio) = 1/1] was novolaked with formaldehyde. This was reacted with epichlorohydrin to form glycidyl ether. Epoxy equivalent: 159, softening temperature: 110 ° C

[Epoxy Resin F] A mixture of 9,10-dihydroxyanthracene and 1,8,10-trihydroxyanthracene [mixing ratio (weight ratio) = 1/1] was novolaked with formaldehyde. This was reacted with epichlorohydrin to form glycidyl ether. Epoxy equivalent: 159, softening temperature: 102 ° C

[Epoxy Resin G] o-Cresol Novolac Epoxy Resin Epoxy Equivalent: 195, Softening Temperature 80 ° C.

[Curing Agent A] 1, represented by the following structural formula:
4-Dihydroxyanthracene was novolaked with formaldehyde.

[Chemical 10] Hydroxyl equivalent: 119, Softening temperature: 140 ° C

[Curing agent B] 9, which is represented by the following structural formula:
10-Dihydroxyanthracene was novolaked with formaldehyde.

[Chemical 11] Hydroxyl equivalent: 119, Softening temperature: 138 ° C

[Curing agent C] 1, represented by the following structural formula:
2,10-Trihydroxyanthracene was novolaked with formaldehyde.

[Chemical 12] Hydroxyl equivalent: 86, softening temperature: 122 ° C

[Curing agent D] 1-represented by the following structural formula
Monohydroxyanthracene was novolaked with formaldehyde.

[Chemical 13] Hydroxyl equivalent: 206, Softening temperature: 104 ° C

[Curing agent E] A mixture of 1,4-dihydroxyanthracene and 1,2,10-trihydroxyanthracene [mixing ratio (weight ratio) = 1/1] was novolaked with formaldehyde. (Hydroxyl equivalent: 103, softening temperature: 129 ° C)

[Curing agent F] A mixture of 9,10-dihydroxyanthracene and 1,8,10-trihydroxyanthracene [mixing ratio (weight ratio) = 1/1] was novolaked with formaldehyde. (Hydroxyl equivalent: 103, softening temperature: 130 ° C)

[Curing agent G] Phenol novolac resin. Hydroxyl equivalent: 105, softening temperature: 80 ° C

[0054]

Examples 1 to 34, Comparative Examples 1 to 3 Silicone compounds a to d, epoxy resins A to G and curing agents A to G,
The respective components shown in Tables 1 to 6 below are blended in the proportions shown in the same table, melt-kneaded for 3 minutes with a mixing roll machine (temperature 100 ° C.), cooled and solidified, and then pulverized to obtain a desired powdery semiconductor. An epoxy resin composition for sealing was obtained.

[0055]

[Table 1]

[0056]

[Table 2]

[0057]

[Table 3]

[0058]

[Table 4]

[0059]

[Table 5]

[0060]

[Table 6]

Using the epoxy resin compositions obtained in the above Examples and Comparative Examples, semiconductor devices were obtained by transfer molding (conditions: 175 ° C. × 2 minutes, 175 ° C. × 5 hours post-curing). It was This package is an 80-pin QFP (quad flat package,
The size is 20 × 14 × 2 mm) and the die pad size is 8 × 8 mm.

The semiconductor device thus obtained was subjected to a thermal cycle test (TCT test) of −50 ° C./5 minutes to 150 ° C./5 minutes. Also, after leaving it in a thermostat of 85 ° C / 85% relative humidity to absorb moisture, 260 ° C
The test of immersing in the solder melt for 10 seconds was conducted. The results are shown in Tables 7 to 10 below.

[0063]

[Table 7]

[0064]

[Table 8]

[0065]

[Table 9]

[0066]

[Table 10]

From the results shown in Tables 7 to 10, it is understood that the TCT test of the example product and the crack resistance during immersion in the solder melt are significantly superior to those of the conventional product as the comparative example.

Continuation of front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location H01L 23/31 (72) Inventor Koichi Ochi 7-1-5 Minami Kasugaoka, Ibaraki City, Osaka Prefecture

Claims (8)

[Claims] 1. A novolak body containing at least one of the following (A), (B) and (C) as a main component, wherein (A), (B) and (C) have a hydroxyl group equivalent. 80 ~
A novolac body having a characteristic of being in the range of 220 and having a softening temperature of 70 to 200 ° C. (A) A novolac form of monohydroxyanthracene. (B) A novolac form of dihydroxyanthracene. (C) A novolac form of trihydroxyanthracene. 2. An epoxy resin obtained by reacting the novolak body according to claim 1 with epichlorohydrin. 3. An epoxy resin composition for semiconductor encapsulation, which comprises an epoxy resin, a curing agent comprising the novolak body according to claim 1, and a curing accelerator. 4. An epoxy resin composition for semiconductor encapsulation, comprising the epoxy resin according to claim 2, a curing agent, and a curing accelerator. 5. An epoxy resin composition for semiconductor encapsulation, comprising the epoxy resin according to claim 2, a curing agent comprising the novolak body according to claim 1, and a curing accelerator. 6. A semiconductor device obtained by encapsulating a semiconductor element using the epoxy resin composition for encapsulating a semiconductor according to claim 3. 7. A semiconductor device obtained by encapsulating a semiconductor element using the epoxy resin composition for encapsulating a semiconductor according to claim 4. 8. A semiconductor device obtained by encapsulating a semiconductor element using the epoxy resin composition for encapsulating a semiconductor according to claim 5.